QuakeIndex

Earthquake · reviewed by a seismologist

M 1.6md

Mona Passage

Yes. A magnitude 1.6 earthquake was recorded in Mona Passage, 13 km (8 mi) ESE of Mayagüez, PR, at 6:33 pm AST on 1 August 2019 (22:33 UTC), 15 km deep.

13 km (8 mi) ESE of Mayagüez, PR · 105 km (65 mi) WSW of San Juan, PR

· 15 km deep · released about 8.7 lb of TNT

10 km30 km60 km120 km N San Germán Municipio 7 kmLas Marías Municipio 8 kmMaricao Municipio 10 kmHormigueros Municipio 10 kmSabana Grande Municipio 12 kmAñasco Municipio 17 kmSan Sebastián Municipio 19 kmYauco Municipio 20 kmLares Municipio 20 km
Distance rings around the epicentre, with the nearest towns at their true direction and later quakes as coloured dots. Not a shaking map — see the USGS ShakeMap for that.
When
Magnitude
M 1.6 (md)
Depth
15 km below the surface
Felt
no reports yet
Nearest
San Germán Municipio, 7 km S
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2659 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.

At this magnitude and depth it was probably too small to be felt, even directly above it. Estimated from magnitude, depth and distance with the intensity equation USGS Did You Feel It? uses; felt reports, where there are any, are the measurement.

Earthquakes near other towns within 30 km: Maricao, San Germán, Sabana Eneas, Hormigueros, Sabana Grande, Monte Grande.

How big was it?

This earthquake released about 8.7 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.6 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 1,700,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 1,200,000× the energy of this one
  3. Around the size people start to feel M 3.0 110× the energy of this one
  4. This earthquake M 1.6 about 8.7 lb of TNT

Energy from the Gutenberg–Richter relation (log10E = 1.5M + 4.8), rounded to two figures; bar length is magnitude, which is already a logarithm of energy. Magnitudes of past earthquakes from the USGS catalogue.

Where

Epicentre 18.1683, -67.0258. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
San Germán Municipio, PR 7 km (4 mi) S earthquakes near San Germán Municipio
Las Marías Municipio, PR 8 km (5 mi) NE earthquakes near Las Marías Municipio
Maricao Municipio, PR 10 km (6 mi) E earthquakes near Maricao Municipio
Hormigueros Municipio, PR 10 km (6 mi) WSW earthquakes near Hormigueros Municipio
Sabana Grande Municipio, PR 12 km (8 mi) SE earthquakes near Sabana Grande Municipio
Añasco Municipio, PR 17 km (11 mi) NW earthquakes near Añasco Municipio

Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.

Aftershocks so far

40 earthquakes have been recorded within 50 km since this one.

  1. 2.1 12 km NNW of Rincón, Puerto Rico
  2. 1.9 3 km SW of Las Marías, Puerto Rico
  3. 1.7 10 km N of Yauco, Puerto Rico
  4. 1.8 1 km ENE of Mayagüez, Puerto Rico
  5. 1.9 10 km NNE of Isabela, Puerto Rico
  6. 2.1 2 km SW of Maricao, Puerto Rico
  7. 1.6 12 km WNW of Puerto Real, Puerto Rico
  8. 2.2 1 km NNW of Pole Ojea, Puerto Rico
  9. 1.6 8 km W of Mayagüez, Puerto Rico
  10. 2.0 2 km S of Mayagüez, Puerto Rico
  11. 1.9 1 km ENE of La Playa, Puerto Rico
  12. 1.8 2 km WNW of Guayanilla, Puerto Rico
  13. 1.8 7 km SW of Jayuya, Puerto Rico
  14. 1.6 3 km SW of Puerto Real, Puerto Rico
  15. 2.5 4 km E of Mayagüez, Puerto Rico

Counted from the QuakeIndex database, which ingests the USGS feed every 30 seconds · as of . QuakeIndex does not forecast aftershocks. When USGS issues an operational aftershock forecast it appears on the USGS event page.

On USGS

QuakeIndex does not issue warnings. For earthquake early warning see ShakeAlert.